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                                                                     Exhibit 4.3

          Second SUPPLEMENTAL INDENTURE, dated as of April 22, 2004, to the
Indenture dated as of July 5, 2000, among CHC Helicopter Corporation, a company
organized under the laws of Canada (the "Company"), the subsidiary guarantors
party thereto (the "Guarantors"), and The Bank of New York, a New York banking
corporation, as trustee (the "Trustee"), as supplemented and amended by a first
supplemental indenture dated as of November 30, 2000 (the "First Supplemental
Indenture").

                              W I T N E S S E T H :

          WHEREAS, the Company and the Trustee have heretofore executed and
delivered each of the Indenture and the First Supplemental Indenture, and the
Company has issued pursuant to the Indenture (euro)145,000,000 aggregate
principal amount of 11 3/4% Senior Subordinated Notes due 2007 (the "Notes");

          WHEREAS, Section 902 of the Indenture provides that the Company, the
Guarantors and the Trustee may, with the consent of the Holders of not less than
a majority in principal amount of all outstanding Notes that are affected
thereby, enter into a supplemental indenture for the purpose of adding any
provisions to or changing in any manner or eliminating any of the provisions of
the Indenture;

          WHEREAS, the Company has offered to purchase for cash all of the
outstanding Notes upon the terms and subject to the conditions set forth in the
Offer to Purchase and Consent Solicitation Statement, dated April 7, 2004 from
each Holder of such Notes (as the same may be amended or supplemented from time
to time, the "Offer");

          WHEREAS, the consent solicitation is conditioned upon, among other
things, certain amendments to the Indenture and to the Notes as set forth in
Article Two of this Supplemental Indenture (the "Amendments") having been
approved by Holders of a majority of the outstanding principal amount of the
Notes, provided that all validly tendered Notes are accepted for purchase
pursuant to the Offer and provided that pursuant to Section 4.01 hereof the
Amendments will not become operative until the opening of business on the
Initial Acceptance Date (as defined in the Offer);

          WHEREAS, the Company has received and delivered to the Trustee the
requisite consents from Holders of a majority of the outstanding principal
amount of the Notes to effect the Amendments;

          WHEREAS, the Company has been authorized by a resolution of its Board
of Directors to enter into this Supplemental Indenture; and

          WHEREAS, all other acts and proceedings required by law, by the
Indenture and by the certificate of incorporation and by-laws of the Company to
make this Supplemental Indenture a valid and binding agreement for the purposes
expressed herein, in accordance with its terms, have been duly done and
performed;

          NOW, THEREFORE, in consideration of the premises and the covenants and
agreements contained herein, and for other good and valuable consideration the
receipt of which is hereby acknowledged, the Company and the Trustee hereby
agree as follows:

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                                   ARTICLE ONE

SECTION                  1.01. Second Supplemental Indenture.

          This Second Supplemental Indenture is supplemental to, and is entered
into in accordance with Section 902 of, the Indenture, and except as modified,
amended and supplemented by this Second Supplemental Indenture, the provisions
of the Indenture are in all respects ratified and confirmed and shall remain in
full force and effect; and

SECTION                  1.02. Definitions.

          Capitalized terms used in this Supplemental Indenture and not
otherwise defined herein shall have the meanings assigned to such terms in the
Indenture.

                                   ARTICLE TWO

SECTION                  2.01. Amendment to Table of Contents.

          The Table of Contents of the Indenture is amended by:

          (i)     deleting the following headings: "Consolidation, Merger,
Conveyance, Transfer or Lease"; "Company May Consolidate, Etc., Only on Certain
Terms"; "Subsidiary Guarantors May Consolidate, Etc., Only on Certain Terms";
"Successor Substituted", and in each such instance, inserting in lieu thereof
the phrase "[intentionally omitted]";

          (ii)    deleting the heading "Corporate Existence" and inserting in
lieu thereof the phrase "[intentionally omitted]";

          (iii)   deleting the heading "Payment of Taxes and Other Claims" and
inserting in lieu thereof the phrase "[intentionally omitted]";

          (iv)    deleting the heading "Maintenance of Properties" and inserting
in lieu thereof the phrase "[intentionally omitted]";

          (v)     deleting the heading "Statement by Officers as to Default" and
inserting in lieu thereof the phrase "[intentionally omitted]";

          (vi)    deleting the heading "Limitation on Indebtedness" and
inserting in lieu thereof the phrase "[intentionally omitted]";

          (vii)   deleting the heading "Limitation on Restricted Payments" and
inserting in lieu thereof the phrase "[intentionally omitted]";

          (viii)  deleting the heading "Limitation on Issuance and Sale of
Capital Stock by Restricted Subsidiaries" and inserting in lieu thereof the
phrase "[intentionally omitted]";

          (ix)    deleting the heading "Limitation on Transaction with
Affiliates" and inserting in lieu thereof the phrase "[intentionally omitted]";

                                        2
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          (x)     deleting the heading "Limitation on Liens" and inserting in
lieu thereof the phrase "[intentionally omitted]";

          (xi)    deleting the heading "Restriction on transfer of Assets to
Subsidiaries" and inserting in lieu thereof the phrase "[intentionally
omitted]";

          (xii)   deleting the heading "Limitations on Guarantees of
Indebtedness by Restricted Subsidiaries" and inserting in lieu thereof the
phrase "[intentionally omitted]";

          (xiii)  deleting the heading "Limitation on Dividends and Other
Payments Restrictions Affecting Restricted Subsidiaries" and inserting in lieu
thereof the phrase "[intentionally omitted]";

          (xiv)   deleting the heading "Limitation on Sale and Leaseback
Transactions" and inserting in lieu thereof the phrase "[intentionally
omitted]";

          (xv)    deleting the heading "Limitation on senior subordinated
Indebtedness" and inserting in lieu thereof the phrase "[intentionally
omitted]";

          (xvi)   deleting the heading "Limitation on Unrestricted Subsidiaries"
and inserting in lieu thereof the phrase "[intentionally omitted]";

          (xvii)  deleting the heading "Reports" and inserting in lieu thereof
the phrase "[intentionally omitted]"; and

          (xviii) deleting the following sub-headings under the heading "SECTION
101 -- Definitions": "Acquired Indebtedness"; "Average Life"; "Canadian Sale";
"Consolidated Adjusted Net Income"; "Consolidated Fixed Charge Coverage Ratio";
"Consolidated Interest Expense"; "Consolidated Net Worth"; "Consolidated
Non-cash Charges"; "Consolidated Tax Expense"; "Disinterested Director";
"Material Permit"; "Net Cash Proceeds"; "Non-Recourse Debt"; "Ordinary Shares";
"Permitted Joint Venture"; "Permitted Joint Venture Business"; "Permitted Sale
and Leaseback Transaction"; "Purchase Money Obligations"; and "Surviving
Guarantor Entity".

SECTION                  2.02. Amendment of Certain Definitions in Article One.

          Section 101 of the Indenture is amended by deleting the definitions
"Acquired Indebtedness"; "Average Life"; "Canadian Sale"; "Consolidated Adjusted
Net Income"; "Consolidated Fixed Charge Coverage Ratio"; "Consolidated Interest
Expense"; "Consolidated Net Worth"; "Consolidated Non-cash Charges";
"Consolidated Tax Expense"; "Disinterested Director"; "Material Permit"; "Net
Cash Proceeds"; "Non-Recourse Debt"; "Ordinary Shares"; "Permitted Joint
Venture"; "Permitted Joint Venture Business"; "Permitted Sale and Leaseback
Transaction"; "Purchase Money Obligations"; and "Surviving Guarantor Entity" in
their entirety.

SECTION                  2.03. Amendment of Certain Provisions in Article Five.

          (i)     Section 501(v) of the Indenture is amended by deleting the
text of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

                                        3
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          (ii)    Section 501(vi) of the Indenture is amended by deleting the
text of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (iii)   Section 501(viii) of the Indenture is amended by deleting the
text of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (iv)    Section 501(ix) of the Indenture is amended by deleting the
text of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (v)     Section 501(xi) of the Indenture is amended by deleting the
text of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

SECTION                  2.04. Amendment of Article Eight.

          Article Eight of the Indenture is amended by deleting the text of such
Article in its entirety and inserting in lieu thereof the phrase "[intentionally
omitted]"

SECTION                  2.05. Amendment of Certain Provisions in Article Ten.

          (i)     Section 1004 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (ii)    Section 1005 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (iii)   Section 1006 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (iv)    Section 1007 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (v)     Section 1008 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (vi)    Section 1009 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (vii)   Section 1010 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (viii)  Section 1011 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (ix)    Section 1012 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (x)     Section 1015 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

                                        4
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          (xi)    Section 1016 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (xii)   Section 1017 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (xiii)  Section 1018 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (xiv)   Section 1019 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (xv)    Section 1020 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

          (xvi)   Section 1022 of the Indenture is amended by deleting the text
of such Section in its entirety and inserting in lieu thereof the phrase
"[intentionally omitted]".

SECTION                  2.06. Amendment of Certain Provisions in Article
                         Eleven.

          (i)     Section 1103 of the Indenture is amended by deleting "60 days"
and inserting in lieu thereof "15 days".

          (ii)    Section 1104 of the Indenture is amended by deleting "at least
30" and inserting in lieu thereof "at least 3".

          (iii)   Section 1105 of the Indenture is amended by

                  (a) deleting the phrase "not less than 30 nor more than 60
          days prior to the Redemption Date" and inserting in lieu thereof the
          phrase "not less than 3 nor more than 60 days prior to the Redemption
          Date" and

                  (b) deleting the phrase "that the Company shall deliver to the
          Trustee, at least 45 days prior " and inserting in lieu thereof the
          phrase "that the Company shall deliver to the Trustee, at least 18
          days prior ".

SECTION                  2.07. Amendment of Certain Provisions in the Notes.

          (i)     Paragraph 5 on the Reverse Side of the Notes is amended by
deleting the phrase "Notice of a redemption will be mailed, first-class postage
prepaid, at least 30 days but not more than 60 days before the Redemption Date
to each Holder to be redeemed at such Holder's last address as it appears in the
Note Register" and inserting in lieu thereof the phrase "Notice of a redemption
will be mailed, first-class postage prepaid, at least 3 days but not more than
60 days before the Redemption Date to each Holder to be redeemed at such
Holder's last address as it appears in the Note Register".

          (ii)    Paragraph 12 on the Reverse Side of the Notes is amended by
deleting the phrase "(i) Indebtedness; (ii) Restricted Payments; (iii) issuances
and sales of Capital Stock of

                                        5
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Restricted Subsidiaries; (iv) transactions with Affiliates; (v) Liens; (vi)
purchase of Notes upon a Change in Control; (vii) disposition of proceeds of
Asset Sales; (viii) guarantees of Indebtedness by Restricted Subsidiaries; (ix)
dividend and other payment restrictions affecting Restricted Subsidiaries; (x)
merger and certain transfers of assets; and (xi) limitation on Unrestricted
Subsidiaries", and inserting in lieu thereof the phrase "(i) purchase of Notes
upon a Change in Control and (ii) disposition of proceeds of Asset Sales".

SECTION                  2.08. Other Amendments

          All other definitions in the Indenture that are used exclusively in
the sections and clauses deleted pursuant to this Article Two and any references
in the Indenture to the sections deleted pursuant to this Article Two hereby are
deleted.

                                  ARTICLE THREE

SECTION                  3.01. Effectiveness of Amendments to Indenture.

          Notwithstanding any other provision of this Supplemental Indenture,
(i) this Supplemental Indenture shall be effective upon its signing by the
parties hereto and (ii) the Amendments shall not be operative until the opening
of business on the Initial Acceptance Date, provided that all validly tendered
Notes are accepted for purchase pursuant to the Offer.

SECTION                  3.02. Continuing Effect of Indenture.

          Except as expressly provided herein, all of the terms, provisions and
conditions of the Indenture and the Debentures outstanding thereunder shall
remain in full force and effect.

SECTION                  3.03. Construction of Supplemental Indenture.

          The Supplemental Indenture is executed as and shall constitute an
indenture supplemental to the Indenture and shall be construed in connection
with and as part of the Indenture. This Supplemental Indenture shall be governed
by and construed in accordance with the laws of the State of New York.

SECTION                  3.04. Trust Indenture Act Controls.

          If any provision of this Supplemental Indenture limits, qualifies or
conflicts with another provision of this Supplemental Indenture or the Indenture
that is required to be included by the Trust Indenture Act of 1939 as in force
at the date as of which this Supplemental Indenture is executed, the provision
required by said Act shall control.

SECTION                  3.05. Trustee Disclaimer.

          The recitals contained in this Supplemental Indenture shall be taken
as the statements of the Company, and the Trustee assumes no responsibility for
their correctness. The Trustee makes no representations as to the validity or
sufficiency of this Supplemental Indenture.

                                        6
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SECTION                  3.06. Counterparts.

          This Supplemental Indenture may be executed in any number of
counterparts, each of which so executed shall be deemed to be an original, but
all such counterparts shall together constitute but one and the same instrument.

SECTION                  3.07. Acceptance.

          The Trustee accepts the Indenture, as supplement by this Second
Supplemental Indenture, and agrees to perform the same upon the terms and
conditions set forth therein as so supplemented.

SECTION                  3.08. Severability.

          In case any provision in this Second Supplemental Indenture shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

SECTION                  3.09. Effect of Headings.

          The Article and Section headings herein are for convenience only and
shall not affect the construction hereof.

                                        7
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          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed, all as of the day and year first above written.

                           CHC HELICOPTER CORPORATION


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC HELICOPTERS INTERNATIONAL INC.


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC SCOTIA LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           BOND HELICOPTER SERVICES LTD.


                           By
                              --------------------------------
                              Name:
                              Title:

 <Page>

                           BRINTEL HELICOPTERS LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           BRINTEL HOLDINGS LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC HELICOPTERS (BARBADOS) LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           CANADIAN HELICOPTERS (U.K.) LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC HELICOPTER HOLDINGS LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:

<Page>

                           CHC LEASING (BARBADOS) LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           COURT HELICOPTER SERVICES PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           COURT AIR PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC HELICOPTERS (MAURITIUS) LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           CHC HELICOPTERS (AFRICA) PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:

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                           FLIGHT HANDLING LIMITED


                           By
                              --------------------------------
                              Name:
                              Title:


                           LLOYD BASS STRAIT HELICOPTERS PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           LLOYD HELICOPTERS INTERNATIONAL
                           PTY. LTD., in its individual
                           capacity and as trustee of
                           THE AUSTRALIAN HELICOPTERS TRUST


                           By
                              --------------------------------
                              Name:
                              Title:


                           LLOYD HELICOPTERS PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:

<Page>

                           LLOYD HELICOPTER SERVICES LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           LLOYD HELICOPTER SERVICES PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           LLOYD OFFSHORE HELICOPTERS PTY. LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           MANAGEMENT AVIATION LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           NORTH DENES AERODROME LTD.


                           By
                              --------------------------------
                              Name:
                              Title:

<Page>

                           VIKING HELICOPTERS LTD.


                           By
                              --------------------------------
                              Name:
                              Title:


                           THE BANK OF NEW YORK, as Trustee


                           By
                              --------------------------------
                              Name:
                              Title: